EP2329147B1 - Pumping device - Google Patents

Description

The invention relates to a pump device with a pulsator as a drive element for a main pump head, which is located in a delivery line and whose working space is provided with a suction-side check valve and a pressure-side check valve, according to the preamble of claim 1.

In the sense of the present disclosure of the invention, a membrane pulsator is to be understood such that it corresponds to a piston membrane pump, which does not necessarily have check valves on the suction and pressure side, but otherwise generally has all the features of a piston membrane pump. A person skilled in the art understands a piston diaphragm pump to be a piston pump coupled to a diaphragm, the deflection of the piston being transmitted to the diaphragm via a hydraulic coupling. Membrane pulsators can in particular, like piston diaphragm pumps, have a preferably diaphragm-controlled refill and / or venting device for the hydraulic fluid, such as that from the EP 0 085 725 A1 is known.

In particular, the invention relates to a pump device with a pulsator, in particular a membrane pulsator, as a drive element for a main pump head, which is located in a delivery line and whose working space is provided with a suction-side check valve and a pressure-side check valve. The work area of the pulsator is directly connected to the work area of the main pump head via a pendulum line filled with the pumped medium in such a way that the pulsator oscillates the pumped medium from the delivery line into the work area of the main pump head or presses it out of the work area. The pump device according to the invention is particularly well suited for conveying suspensions, such as mixtures of biomass and supercritical water, and in particular for high pressures and temperatures.

Pumps of this type are out EP 0919724 B1 . US 3,216,360 and EP 1898093 A1 known. Here, a main pump head located in the delivery line is driven by another pump head, which is referred to as a pulsator. Such a pump device is also referred to as a "remote head" pump. Pump devices of this type are typically used for pumping liquids with a high solids content and high temperatures. However, the known pumps cannot readily be used with particularly aggressive delivery media, such as supercritical aqueous solutions, in particular when processes with a very high throughput are present at high temperatures and high pressures.

Another type of pump device, namely a diaphragm metering pump for metering a shower gas, is in the US 2004/062662 A1 described. This pump has a pump head with a product chamber with an inlet end with an inlet valve and an outlet end with an outlet valve. A sliding membrane element defines a boundary of the product chamber. The membrane element can be moved back and forth to cause pump displacements. An exhaust side is located downstream of the exhaust valve. A passage is arranged in fluid communication between the delivery side and the product chamber. A valve is located in the passage. The valve is opened intermittently to allow the liquid to flow back into the product chamber in an amount that can be used to remove the gas from the product chamber to avoid loss of ventilation.

The invention has for its object to provide a pump device of the type mentioned, which can be used for pumping aggressive fluids at high temperature, and yet works at low cost with high reliability, which is why in particular an entry of solid particles in the pulsator can be avoided should.

This object is achieved by a pump device according to the features of independent claim 1. Advantageous embodiments of the invention are specified in the dependent claims. According to the invention, a pump device with a pulsator as a drive element for a main pump head, which is located in a delivery line and whose work space is provided with a suction-side check valve and a pressure-side check valve, is specified, the work space of the pulsator being connected to the work space of the main pump head via a pendulum line filled with the conveyed medium is connected in such a way that the pulsator sucks conveying medium from the delivery line into the working chamber of the main pump head in an oscillating manner or presses it out of the working chamber, a vent valve being provided for venting the working chamber of the pulsator, the vent valve being a time-controlled valve and / or a pressure-controlled one Double seat valve and a device for introducing a liquid into the working space of the pulsator and / or the pendulum line is provided.

The use of a time-controlled valve and / or a pressure-controlled double-seat valve has the advantage that the time in which the valve is open for venting can be kept very short, as a result of which undesirable secondary flows can be avoided, which increase the entry of solid particles into the pulsator could result.

The introduction of liquid into the working area of the pulsator or the refilling of pumped medium into the working area to compensate for losses, for example by venting the working area, has the advantage that liquid balance does not have to take place from the driven main pump head and thus no solid particles from the main pump head to be transported to the pulsator. The liquid is preferably water and / or delivery medium and / or another suitable liquid.

The device for introducing a liquid into the work space of the pulsator and / or the pendulum line preferably comprises a time and / or pressure-controlled refill valve and / or a refill reservoir.

The time and / or pressure-controlled refill valve or vent valve is preferably time and / or pressure controlled such that after a start-up phase of the process the refill valve or vent valve is closed and / or the upper limit value for closing the time and / or pressure-controlled refill valve or vent valve is increased after a start-up phase of the process and / or after a start-up phase of the process the lower limit value for closing the time and / or pressure-controlled refill valve or vent valve is lowered.

The pressure which is applied to the refill reservoir preferably corresponds essentially to the pressure in the working space of the pulsator.

The refill valve between the work space and the refill reservoir is preferably a time and / or pressure-controlled valve. The working space of the pulsator is preferably connected to the suction side of the delivery line via the and / or a further vent valve.

Preferably, the suction side of the delivery line for automatic venting is advantageously arranged above the venting valve.

Alternatively or additionally, the working space of the pulsator is preferably connected to the pressure side of the delivery line via the and / or a further vent valve.

The vent valve is preferably positively controlled in connection with a return pump, in particular timed.

Alternatively or additionally, the working area of the pulsator is preferably connected via the and / or a further vent valve to a refill reservoir to compensate for leakage shrinkage in the working area of the pulsator and / or the pendulum line.

As an alternative or in addition, the working space of the pulsator is preferably connected via the and / or a further vent valve to a collecting container for collecting and for possibly returning the conveyed medium emerging during the venting.

The valve is preferably time and / or pressure controlled in such a way that it is closed at least above a certain pressure. The pulsator generates a continuously alternating pressure in the work area with a pressure phase and a suction phase. In order to prevent a weakening of the flow from the pendulum line to expel solid particles that may have been sucked in, at least a certain pressure in the work area should not be vented in order to prevent a pressure drop in the work area, albeit a small one, and thus a reduction in the flow from the pendulum line ,

The valve is preferably time and / or pressure controlled such that it is closed at least below a certain pressure.

As an alternative or in addition, venting below a certain pressure in the pulsator's working space is preferably avoided, because the, albeit small, pressure drop would result in greater suction power and thus a stronger flow into the pendulum line, which could suck more solid particles into the pendulum line. Therefore, the valve is preferably closed at least below a certain pressure in the work area.

The venting preferably takes place only in the time ranges between the suction and the pressure phase, where there is essentially little or no flow of the delivery fluid into the pendulum line. This can prevent the flow of solid particles into the pendulum line.

The pump device preferably has a refill reservoir for refilling the conveyed medium, to which a pressure is applied which essentially corresponds to the system pressure.

In all embodiments of the invention, the pendulum line is preferably provided with cooling.

In all embodiments of the invention, the pulsator is preferably arranged above the main pump head. Additionally or alternatively, the pendulum line is preferably aligned falling from the pulsator to the main pump head. Such embodiments of the invention have the advantage that gravity additionally counteracts the entry of solid particles through the pendulum line into the pulsator.

The pendulum line is preferably provided with a depression as a receiving space for solid particles in the conveying medium.

The working space of the pulsator is preferably at least temporarily acted upon by a compensating medium to compensate for leakage shrinkage.

The pendulum line is preferably divided into at least one section into at least two parallel sections.

The pendulum line is preferably also divided over its entire course, i.e. that, for example, two or more parallel pendulum lines are provided.

These embodiments of the invention have the advantage that by providing a corresponding control, for example in the suction phase, the at least two subsections are opened and in the printing phases at least one subsection (in the case of two subsections, preferably one and the other subsection alternately) at least partially and preferably completely at least is closed during part of the printing phase in order to prevent deposits of solid particles in the partial sections due to the higher outflow speed thus resulting in the other partial section (s).

The volume of the parallel sections of the pendulum line or the volume of the parallel pendulum lines is preferably at least as large as or preferably larger than the stroke volume of the pulsator. This development of the invention has the advantage that it is very likely that solid particles can escape into the remaining pendulum line and / or the pulsator.

Control valves are preferably provided for at least partially opening and closing the sections of the pendulum line or the parallel pendulum lines.

A sensor system is preferably provided in order to synchronize the timing of the control valves with the respective phase position of the pulsator membrane. For example, a sensor and / or switch is provided which switches the control valve in at least one end position of the membrane of the pulsator. Alternatively or additionally, a sensor and / or switch is provided for the other membrane system in order to switch the control valve. Alternatively, the control valves are also put into a closed position or partially closed position only during part of the pressure phase. It would also be conceivable to at least partially close different control valves in succession during a printing phase.

The pendulum line is preferably divided in the area in front of the main pump head into a plurality of lines connected in parallel, preferably two lines connected in parallel, which are at least partially and preferably completely at least partially closable by a time and / or pressure-controlled valve.

The time and / or pressure control is preferably set in such a way that all lines are open for as long as possible during the suction phase, so that the flow adjusts to the different ones in parallel Lines distributed, while in the pressure phases alternately a partial line with the full pressure and thus a much higher flow rate. As a result, the entry of solid particles into the pendulum line should be avoided.

The main pump head preferably has at least two suction-side check valves connected in parallel.

This embodiment of the invention has the advantage that a higher flow velocity is generated in the line section between the outlets of the two suction-side check valves during the pressure phase, so that the risk of solid particles entering the pendulum line from the suction side downstream of the flow direction during the pressure phase Check valve is reduced.

The cross section of the line receiving the downstream suction-side check valve in relation to the flow direction during the pressure phase is preferably larger than the cross section of the line receiving the other suction-side check valve.

This is the preferred embodiment of this preferred embodiment, because then more solid particles are conveyed through the line, which offers increased security against the entry of solid particles into the pendulum line. Alternatively, the cross sections of the two lines could also be the same size or more than two lines and a corresponding number of check valves on the suction side could be provided. It would also be conceivable to have a larger cross section of the line receiving upstream suction-side check valve in relation to the direction of flow during the pressure phase, which still offers an advantage, albeit a smaller one, than the designs with only one suction-side check valve.

A separating piston is preferably arranged in the pendulum line.

These embodiments of the invention have the advantage that the separating piston prevents solid particles from passing through the pendulum line from the main pump head to the pulsator.

The above-mentioned embodiments of the pump device according to the invention are preferably designed with a double-acting pulsator and two pump circuits controlled in opposite directions.

The pulsator is preferably designed as a double-acting pulsator, one side of which is designed as a drive element for the main pump head, and the other side of which is acted upon by a pressure which essentially corresponds to the system pressure.

Such embodiments of the invention with a double-acting pulsator for driving two mutually controlled pump circuits are preferred, since this enables uniform delivery. Furthermore, the pulsator can be driven at high suction pressures of, for example, 250 bar with a drive designed for significantly lower pressures, for example if a double-acting piston is used, which only the differential pressure between the pressure during the pressure phase in one half of the pulsator and the pressure during the Must overcome suction phase in the other half of the pulsator. This advantage also applies to double-acting pulsators for driving only one pump circuit when pressure is applied to the other side of the pulsator, which does not drive the pump circuit. Advantageously, in embodiments of the invention with a refill reservoir for the membrane control chamber or pulsators, the refill reservoir is pressurized with a pressure that approximately corresponds to the system pressure, so that the drive also takes place during the refill process, which is valve-controlled when the membrane is its rear mechanical system achieved, is not exposed to a higher pressure than the differential pressure between the suction and pressure phases and therefore does not have to be dimensioned larger, and the membrane is not destroyed at the flow channels of its rear mechanical system.

Preferably, a membrane system-controlled refill and / or venting device for hydraulic fluid can be provided in the pulsator, such as that from the EP 0 085 725 A1 is known.

Compensating medium for compensating for leakage shrinkage is preferably present in the diaphragm control chamber in a refill reservoir which is connected to the diaphragm control chamber via a valve, the refill reservoir being pressurized to a pressure which is higher than atmospheric pressure.

This embodiment of the invention has the advantage that the pulsator can be driven by a drive (for example hydraulically, mechanically and / or pneumatically, for example a piston drive), the power of which only has to overcome the pressure difference between the suction and the pressure side. In addition, an impact on the drive, for example the piston, can be prevented by pressurizing the refill reservoir to compensate for leakage in the membrane control chamber. This pressure in the refill reservoir can advantageously correspond approximately to the system pressure. According to a further advantageous embodiment of the invention, a pressure control which is adapted to the system pressure by means of a control loop is provided in the refill reservoir, as is the case, for example, in EP 1 898 093 A1 is described.

The pulsator is preferably constructed in the form of a membrane or tubular membrane.

The pulsator is preferably designed in a piston or plunger construction.

A basic idea of the invention is therefore that the pulsator acts on a main pump head, which is basically designed like a piston pump head, but without the need for a piston. In this way, a standard component that is suitable for high temperatures and pressures can be used as the pump head, which, combined with a standard membrane pulsator, is an inexpensive alternative to the known solutions, while maintaining the principle of a "remote head" pump. The wear is further reduced by the fact that any particles present in the pumped medium do not come into contact with the working area of the pulsator, since the liquid in the pendulum line is only moved back and forth in the circumference of the pump stroke and mixes only slightly with freshly drawn-in liquid. The pulsator can be constructed in membrane or tubular membrane construction as well as in piston or plunger construction. If the pulsator is a membrane pulsator, particles do not get to the membrane. Since high temperatures in the pumped medium also decrease in the course of the pendulum line, membrane pulsators with inexpensive plastic membranes, for example made of PTFE, can also be used in the delivery line at high pressures and high temperatures. Pump devices according to the invention are therefore particularly well suited for conveying biomass in the production of biofuel.

Another advantage is that, due to the ventilation, gases from the pumped medium or air inclusions cannot accumulate in the pump room of the pulsator, but are returned to the process. For this purpose, the entry into the suction-side delivery line is preferably above the ventilation valve, so that the gases exit the working area automatically. Alternatively, there may be a forced ventilation, for example with a time and / or pressure controlled valve.

In order to further relieve the temperature of the membrane pulsator, a preferred development of the invention is that the pendulum line is provided with cooling.

It also proves to be advantageous that the pendulum line is aligned to fall from the membrane pulsator to the main pump head. The particles thus remain in the area of the main pump head and are returned to the delivery line.

Alternatively, it can be advantageous for the pendulum line to be provided with a depression as a receiving space for solid particles in the conveying medium. An area is therefore provided in the pendulum line which lies below the working space of the membrane pulsator, so that the particles collect there due to gravity and do not get into the working space of the pulsator.

It is expedient that the working space of the pulsator is acted upon by a compensating medium to compensate for leakage shrinkage, so that flow through the pendulum line and migration of solid particles to the pulsator are prevented.

In order to further protect the pulsator against solid particles from the pumped medium, a further advantageous embodiment of the invention consists in arranging a separating piston in the pendulum line. This measure separates the part of the pendulum line assigned to the pulsator from the part assigned to the main pump head.

A low drive power is achieved in that there is a double-acting pulsator and two counter-driven pump circuits, which is particularly advantageous when used in recirculation processes with high suction pressures.

Fig. 1

einen Vertikalschnitt durch eine erste Ausführung einer Pumpenvorrichtung;

Fig. 1A

einen der Fig. 1 entsprechenden Vertikalschnitt durch eine weitere erfindungsgemäße Pumpenvorrichtung mit einem doppelt wirkenden Pulsator und zwei gegensinnig angesteuerten Pumpenkreisen. Fig. 2 ein Schaltbild einer aus zwei Pumpenvorrichtungen nach Fig. 1 zusammengesetzten Pumpenkonfiguration gemäß der Erfindung;

Fig. 3

Merkmale weiterer Ausführungen einer erfindungsgemäßen Pumpenvorrichtung .

Fig. 4

ein Fig. 2 entsprechendes Schaltbild einer alternativen erfindungsgemäßen Pumpenkonfiguration;

Fig. 5

ein Fig. 2 entsprechendes Schaltbild einer weiteren alternativen erfindungsgemäßen Pumpenkonfiguration;

Fig. 6

ein Fig. 2 entsprechendes Schaltbild einer weiteren alternativen erfindungsgemäßen Pumpenkonfiguration;

Fig. 7

ein Fig. 2 entsprechendes Schaltbild einer weiteren alternativen erfindungsgemäßen Pumpenkonfiguration;

Fig. 8

Merkmale weiterer Ausführungen einer erfindungsgemäßen Pumpenvorrichtung .

Fig. 9

Merkmale weiterer Ausführungen einer erfindungsgemäßen Pumpenvorrichtung .

Fig. 10

ein Schaltbild einer aus zwei Pumpenvorrichtungen nach Fig. 1 zusammengesetzten Pumpenkonfiguration gemäß der Erfindung;

Fig. 11

ein p-V-Diagramm des zeitlichen Verlaufs des Drucks der Pumpe über dem Hubvolumen mit einer Angabe einer möglichen Nachfüllung während der Druckphase.

Fig. 12

ein p-V-Diagramm des zeitlichen Verlaufs des Drucks der Pumpe über dem Hubvolumen mit einer Angabe einer möglichen Nachfüllung während der Saugphase.

The invention is explained in more detail below on the basis of exemplary embodiments. They show schematically:

Fig. 1

a vertical section through a first embodiment of a pump device;

Fig. 1A

one of the Fig. 1 corresponding vertical section through a further pump device according to the invention with a double-acting pulsator and two pump circuits driven in opposite directions. Fig. 2 a circuit diagram of one of two pump devices Fig. 1 composite pump configuration according to the invention;

Fig. 3

Features of further designs of a pump device according to the invention.

Fig. 4

on Fig. 2 corresponding circuit diagram of an alternative pump configuration according to the invention;

Fig. 5

on Fig. 2 corresponding circuit diagram of a further alternative pump configuration according to the invention;

Fig. 6

on Fig. 2 corresponding circuit diagram of a further alternative pump configuration according to the invention;

Fig. 7

on Fig. 2 corresponding circuit diagram of a further alternative pump configuration according to the invention;

Fig. 8

Features of further designs of a pump device according to the invention.

Fig. 9

Features of further designs of a pump device according to the invention.

Fig. 10

a circuit diagram of one of two pump devices Fig. 1 composite pump configuration according to the invention;

Fig. 11

a pV diagram of the time course of the pressure of the pump over the stroke volume with an indication of a possible refill during the pressure phase.

Fig. 12

a pV diagram of the time course of the pressure of the pump over the stroke volume with an indication of a possible refill during the suction phase.

1

Pumpenvorrichtung

4

Anschluss (für ein Nachfüllreservoir)

5

Druckseite (der Förderleitung)

6

Förderrichtung

7

Anschluss (für die Pendelleitung)

8

Anschluss (für eine Entlüftung)

9

Entlüftungsventil

10

Membranpulsator

11

Hauptpumpenkopf

12

Pendelleitung

12'

Pendelleitung

121

Teilabschnitt der Pendelleitung

122

Teilabschnitt der Pendelleitung (parallel geschaltet zu Teilabschnitt 121 der Pendelleitung)

123

Steuerventil (vorzugsweise ein druck- oder zeitgesteuertes Absperrventil)

124

Steuerventil (vorzugsweise ein druck- oder zeitgesteuertes Absperrventil)

13

Eingang

14

Ausgang

15

Saugseite (der Förderleitung)

16

saugseitiges Rückschlagventil

161

saugseitiges Rückschlagventil (parallel geschaltet zu saugseitigem Rückschlagventil 16)

17

druckseitiges Rückschlagventil

18

Arbeitsraum (des Hauptpumpenkopfes)

20

Arbeitsraum (der Membranpulsator)

21

Förderflüssigkeit

22

Steuereingang (des Hauptpumpenkopfes)

23

Kühlmantel

24

Feststoffteilchen

25

Abschnitt (in der Pendelleitung)

26

Membran

27

Membransteuerraum

28

Kolben

281

Scheibe

29

Motor

30

Nachfüllreservoir

31

Ventil

32

Trennkolben

33

Bereich (auf Seite des Hauptpumpenkopfes)

34

Bereich (auf Seite des Membranpulsators)

35

Verschieberichtung Trennkolben

36

Sammelbehälter

37

Nachfüllventil des Membransteuerraums

38

Hydraulikpumpe

39

Entlüftungsventil des Membransteuerraums

The following reference symbols are used in the description of the exemplary embodiments:

1

pump device

4

Connection (for a refill reservoir)

5

Discharge side (of the delivery line)

6

conveying direction

7

Connection (for the pendulum line)

8th

Connection (for a vent)

9

vent valve

10

Membranpulsator

11

Main pump head

12

compensation line

12 '

compensation line

121

Section of the pendulum line

122

Section of the pendulum line (connected in parallel to section 121 of the pendulum line)

123

Control valve (preferably a pressure or time controlled shut-off valve)

124

Control valve (preferably a pressure or time controlled shut-off valve)

13

entrance

14

output

15

Suction side (of the delivery line)

16

Check valve on the suction side

161

Check valve on the suction side (connected in parallel to check valve 16 on the suction side)

17

check valve on the pressure side

18

Working area (of the main pump head)

20

Working area (the membrane pulsator)

21

pumped liquid

22

Control input (of the main pump head)

23

cooling jacket

24

solid

25

Section (in the pendulum line)

26

membrane

27

Diaphragm control chamber

28

piston

281

disc

29

engine

30

backfill

31

Valve

32

separating piston

33

Range (on the main pump head side)

34

Area (on the side of the membrane pulsator)

35

Separation piston displacement direction

36

Clippings

37

Refill valve of the diaphragm control room

38

hydraulic pump

39

Bleed valve of the diaphragm control room

According to Fig. 1 A pump device 1 has a membrane pulsator 10 serving as a pulsator, a main pump head 11 and a pendulum line 12. The main pump head 11 has an inlet 13 and an outlet 14 for installation in a delivery line, the pressure side of which is designated 5 and the suction side of which is 15. On the inlet side (suction side) there is a suction-side check valve 16 and on the outlet side (pressure side) there is a pressure-side check valve 17. The direction of conveyance is marked with arrow 6. Structurally, the main pump head 11 corresponds to a pump head of a piston pump. However, it has no piston. Rather, its working space 18 is connected directly to a working space 20 of the membrane pulsator 10 via the pendulum line 12. The membrane pulsator 10 is provided with a connection 7 for the pendulum line 12. Furthermore, a connection 8 for ventilation with a ventilation valve 9 ( Fig. 2 ) and a connection 4 for a refill reservoir 30 ( Fig. 2 ) available. Thus, the oscillating stroke of the membrane pulsator 10 via the liquid column in the pendulum line 12 causes the delivery in the main pump head 11.

The pendulum line 12 is filled with liquid 21. It leads via a control input 22 of the main pump head 11 to the working space 20 of the diaphragm pulsator 10. The pendulum line 12 is provided with a cooling system, which is formed by a cooling jacket 23 charged with coolant becomes. In this way, a temperature reduction of, for example, approximately 360 ° C. at the main pump head 11, as is typically the case with the bio mass to be conveyed in the production of bio-fuels, to approximately 100 ° C. on the membrane pulsator 10.

Since the pendulum line 12 contains the conveying liquid 21, which may also have solid particles 24, a section 25 is present in the pendulum line 12, which drops from the membrane pulsator 10 to the main pump head 11 and which opens directly into the working space 18 of the main pump head 11. At its lowest point, the pendulum line 12 is thus at the level of the working space 18 of the main pump head 11. The solid particles 24 remain due to gravity in the working space 18 of the main pump head 11 and do not get into the working space 20 of the membrane pulsator 10. Rather, they become the pressure-side delivery line 5 fed. The membrane pulsator 10 has a membrane 26 which is controlled hydraulically via a membrane control chamber 27. PTFE is preferably suitable as the membrane material. Alternatively, elastomers, metallic materials or composite materials can also be used. The membrane control chamber 27 is acted upon by a piston 28 which is mechanically actuated, for example by a motor 29 ( Fig. 2 ), and / or is driven hydraulically and / or pneumatically, for example by alternately pressurizing the chambers next to the disk 281. To compensate for leaks, there is a refill reservoir 30 filled with a compensating medium which is controlled by a controlled valve 31 ( Fig. 2 ) Emits compensation medium into the working space 20 of the membrane pulsator 10. The feed is in Fig. 2 designated with 4.

With reference to the Fig. 1 and Fig. 2 the function of the pump device is described below. In the Fig. 2 The configuration shown has a double-acting pulsator with two pump devices as shown in Fig. 1 are illustrated on. The pump devices are connected in parallel in two oppositely controlled branches A, B. First, a pumping process is described using a branch. In an initial state, the piston 28 is moved into the membrane control chamber 27 and the membrane 26 is bulged into the working space 20 of the membrane pulsator 10. The pendulum line 12 and the working space 18 of the main pump head 11 are completely filled with liquid. The suction-side check valve 16 and the pressure-side check valve 17 are closed.

If the piston 28 is extended, this causes the diaphragm 26 to flatten out and a negative pressure in the working space 20 of the diaphragm pulsator 10. The negative pressure acts via the pendulum line 12 in the working space 18 of the main pump head 11, so that the suction-side check valve 16 opens and delivery liquid 21 from the suction side 15 of the delivery line is sucked. During the following opposite stroke of the piston 28, when the diaphragm 26 bulges, pressure is generated in the working space 20 of the diaphragm pulsator 10, which acts on the working space 18 of the main pump head 11 via the pendulum line 12. The pressure causes the suction-side check valve 16 to close and the pressure-side check valve 17 to open, so that Delivery liquid 21 is pumped into the pressure side 5 of the delivery line. The oscillating movement of the piston 28 results in a continuous delivery.

Due to the opposite control of two main pump heads 11 by means of a double-acting pulsator 10, which is preferably designed as a diaphragm, the pumping and suction processes with the two circuits A and B overlap in such a way that, especially in recirculation processes with high system pressure and a relatively low differential pressure between suction and pressure line only a low power is required for the drive. Alternatively, each main pump head 11 can be controlled in the same or opposite direction with a single-acting pulsator.

In Fig. 3 a section of a pendulum line 12 'is illustrated as a detail of a second exemplary embodiment. To separate the liquid column in the pendulum line 12 ', a separating piston 32 which is mounted to be longitudinally displaceable according to the double arrow 35 is arranged in the pendulum line 12'. Possibly existing solid particles 24 thereby remain in an area 33 on the side of the main pump head 11 and cannot reach an area 34 on the side of the membrane pulsator. Fig. 1A shows an embodiment with a double-acting pulsator. Fig. 1A corresponds essentially to that in Fig. 1 shown embodiment, wherein the pump device of Fig. 1 basically exists twice and is driven by a common piston 28. The double-acting pulsator is in Fig. 1A shown extremely simplified, ie without drive and without hydraulic reservoirs and their pressurized refill valves. The double-acting piston 28 describes an end position (the membrane 26 is bulged on the right, ie the pressure stroke or the pressure phase is complete; the membrane 26 is flattened on the left, ie the suction stroke or the suction phase is complete).

The in the Figures 2 . 4 . 5 and 6 The embodiments of the invention shown differ essentially only in the different venting or refilling. The same components and features are described with the same reference numerals. Regarding the embodiments of the Figures 4 . 5 and 6 is therefore based on the above description of the embodiment of Fig. 2 and only the differences from this embodiment of the invention are described below.

Fig. 2 shows an embodiment with ventilation in the suction line 15. The refill takes place from a pressure accumulator 30 (with gas cushion) in a time-controlled or pressure-controlled manner during the pressure stroke of the pulsator. The circuit symbol used for the valve 31 describes a controlled check valve in which the closing is prevented when actuated. The pressure in the refill reservoir 30 must be greater than the system pressure. The refill volume flow must be greater than / equal to the leakage flow of the venting process. A subsequent regulation of the storage pressure depending on the changing system pressure is recommended. If necessary, manual control is also possible.

Fig. 4 shows an embodiment with ventilation in the pressure line 5. The refill takes place from a pressure accumulator 30 (with gas cushion) time or pressure controlled during the suction stroke of the pulsator. The circuit symbol used for the valve 31 describes a controlled check valve, in which the opening is prevented when actuated. The pressure in the refill reservoir 30 must be greater than the suction pressure. The refill volume flow must be greater than / equal to the leakage flow of the venting process. A subsequent regulation of the storage pressure depending on the changing suction pressure is recommended. If necessary, manual control is also possible.

Fig. 5 shows an embodiment with a vent into the refill reservoir 30. The refill takes place from a pressure accumulator 30 (with gas cushion) in a time-controlled manner. The symbol for the refill valve 31 shows no specific function.

Fig. 6 shows an embodiment with ventilation in any storage or collection container 36. The refill is carried out from a pressure accumulator 30 (with gas cushion) in a time-controlled manner. The symbol for the refill valve 31 shows no specific function.

Fig. 7 shows an embodiment of the invention of a pump device with a single-acting pulsator. The venting or refilling can, for example, according to the above-mentioned embodiments of the invention Fig. 2 . Fig. 4 . Fig. 5 or Fig. 6 respectively. The vent in the pressure line 5 is shown as an example of one of the possible variants.

In the embodiment of Fig. 7 Instead of the single-acting pulsator, a double-acting pulsator could also be used, the unused side of which is subjected to a pressure which corresponds approximately to the system pressure, for example by means of a pressure accumulator. The advantages of a pressurized refill medium for refilling into the diaphragm control chamber could thus be exploited. In addition, the pressurization of the unused side of the double-acting pulsator has the advantage that a smaller-sized drive can be used if high pressures of, for example, 250 bar have to be overcome by the pump head driven by the pulsator.

Fig. 8 shows a possible design of the main pump head 11 pump devices according to the invention. On the suction side of the main pump head, two check valves 16, 161 on the suction side are provided, which can also have a different size. This embodiment has the advantage that a higher flow velocity is generated in the line section between the two suction-side check valves during the pressure stroke of the pulsator.

The pendulum line 12 has a gradient towards the suction-side check valves 161, 16. During suction, the suction flow is distributed according to the
Cross-sectional conditions on the suction-side check valves 161 and 16. As a result of this during suction, a lower flow takes place in the pendulum line section between these two suction-side check valves than it would be if the entire suction quantity were only sucked in through the suction-side check valve 16.

In the pressure stroke, the entire flows through the pendulum line

Flow rate of the pump. This leads to the fact that a flow is obtained through the pendulum line, which in total is directed more towards the suction-side check valve 16.

This flow could ensure that the deposits from the main flow tend to be pumped back again and again.

Fig. 9 shows a possible design of the pendulum line 12 pump devices according to the invention. The pendulum line is divided into at least one section into at least two subsections 121, 122, which are used for suction at the same time in the suction phases with the help of controlled shut-off valves 123, 124 and can be opened and closed alternately in the pressure phases in order to increase the pressure generated by them Outflow velocity in the sections 121, 122 to prevent deposits of the solid particles.

The filling volume of each section 121, 122 should preferably be at least as large as and preferably larger than the stroke volume of the pulsator. This prevents solid particles from getting behind the control valves in the pressure phase due to the alternate closing.

In a first suction process, each section would initially be filled with particles up to a maximum of half of its volume. The subsequently closed section would possibly keep this state. During the renewed suction process, the partial section would then be completely filled with particles at most, before a complete rinsing out would take place in the printing phase.

At the in Fig. 9 shown execution time-controlled shut-off valves 123, 124 are provided, which should be synchronized exactly with the respective phase position of the pulsator membrane with the aid of sensors.

Fig. 10 shows a further embodiment of the invention. The same parts are provided with the same reference numerals. Reference is made to the description of the above statements. In Fig. 10 the pulsator is shown in somewhat more detail, the drive for the double-acting piston 28 not being shown. The course of the hydraulic channels of the double-acting pulsator is shown in more detail.

The pump device from Fig. 10 has two refill valves 37 of the diaphragm control chamber, which are preferably acted upon by a pressure which approximately corresponds to the system pressure. The pressure is made available by a hydraulic pump 38. Furthermore, two vent valves 39 are provided for venting the membrane control rooms.

The Figures 11 and 12 show schematic PV diagrams that show the time course of the pump pressure over the stroke volume. Starting at the point on the lower left side, you can see very well the steep flank of the pressure rise during the compression phase, the pressure fluctuations due to the valve kinematics, the displacement of the stroke volume (highest pressure at maximum piston speed), as well as the likewise steep decompression phase and the suction phase. (Note: In the present case, the circular process has been shown clockwise in both figures for reasons of illustration.) The dashed line in Fig. 11 shows the required pressure level and a possible time window for a controlled leakage refilling process during the pressure stroke. The average working pressure of the pulsator in the pressure stroke (pD) is slightly higher than the system pressure.

The dashed line in Fig. 12 shows the required pressure level and a possible time window for a controlled leakage refill process during the suction stroke. When refilling during the suction stroke, it is sufficient if the pressure level is slightly above the suction pressure.

Claims (18)

1. Pump device (1) with a pulsator as drive element for a main pump head (11) which lies in a supply line (15) and the working space (18) of which is provided with a check valve (16) on the suction side and a check valve (17) on the pressure side, wherein the working space (20) of the pulsator is connected to the working space (18) of the main pump head (11) via a pendulum line (12) filled with supply medium (21), in such a way that the pulsator draws supply medium (21) oscillatingly from the conveying line (15) into the working space (18) of the main pump head (11) or presses it out of the working space (18), wherein a venting valve (9) is provided for venting the working space (20) of the pulsator, characterised in that the venting valve (9) is a time-controlled valve and/or a pressure-controlled double-seat valve and in that a device is provided for introducing a liquid into the working space of the pulsator and/or the pendulum line (12).
2. Pump device (1) according to claim 1, characterised in that the working space (20) of the pulsator is connected to the suction side (15) of the supply line via the and/or a further vent valve (9).
3. Pump device (1) according to one of the preceding claims, characterised in that the working space (20) of the pulsator is connected to the pressure side (5) of the supply line via the and/or a further vent valve (9).
4. Pump device (1) according to one of the preceding claims, characterised in that the working space (20) of the pulsator is connected via the and/or a further vent valve (9) to a refill reservoir (30) for compensating for loss of leakage in the working space (20) of the pulsator and/or the pendulum line (12).
5. Pump device (1) according to one of the preceding claims, characterised in that the working space (20) of the pulsator is connected via the and/or a further venting valve (9) to a collecting container (36) for collecting and possibly later returning supply medium (21) emerging during venting.
6. Pump device (1) according to one of the preceding claims, characterised in that the pump device comprises a refill reservoir for refilling supply medium, which is subjected to a pressure which essentially corresponds to the system pressure.
7. Pump device according to one of the preceding claims, characterised in that the pendulum line is provided with a cooling system.
8. Pump device according to one of the preceding claims, characterised in that the pulsator is arranged above the main pump head.
9. Pump device (1) according to one of the preceding claims, characterised in that the pendulum line (12) is divided at least in one section into at least two parallel partial sections (121, 122).
10. Pump device (1) according to the preceding claim, characterised in that the volume of the parallel sub-sections (121, 122) of the pendulum line (12) or the volume of the parallel pendulum lines (121, 122) is in each case at least as large as or preferably greater than the stroke volume of the pulsator.
11. Pump device (1) according to claim 9 or 10, characterised in that control valves (123, 124) are provided for at least partially opening and closing the partial sections (121, 122) of the pendulum line (12) or of the parallel pendulum lines.
12. Pump device (1) according to one of the preceding claims, characterised in that the main pump head has at least two suction-side check valves (16, 161) arranged in parallel.
13. Pump device (1) according to the preceding claim, characterised in that the cross-section of the line accommodating the downstream suction side check valve relative to the direction of flow during the pressure phase is larger than the cross-section of the line accommodating the other suction side check valve.
14. Pump device (1) according to one of the preceding claims, characterised in that a separating piston (32) is arranged in the pendulum line (12').
15. Pump device according to one of the preceding claims, characterised in that it is formed with a double-acting pulsator and two oppositely driven pump circuits (A, B).
16. Pump device (1) according to one of the preceding claims, characterised in that the pulsator is designed as a double-acting pulsator, one side of which is designed as a driving element for the main pump head (11) and the other side of which is subjected to a pressure which corresponds substantially to the system pressure.
17. Pump device according to one of the preceding claims, characterised in that the pulsator is of diaphragm or hose-diaphragm construction.
18. Pump device according to one of the preceding claims 1 to 16, characterised in that the pulsator is of piston or plunger design.

Images